ok. I'm new and full of questions. I went to an import only autoshop the other day and the guy i talked to about turboing a spec-v gave very limited info (he was their big time turbo guy too). All he said was that it will be expensive and i basically have 2 types to choose from, a t3 garret and a mitsubishi turbo. my question is though, not what kind of turbo, but can my engine handle the power of it. I know and sr20 motor can handle the boost, but will my block be able to handle up to 8psi without cracking or blowing up on me? oh, one more thing, i came to this forum for more reliable info than the b15 forum.

Yeah...that website is a little limited sometimes on info. The new QR25 motor is going to be a challenge to put a turbo on. It has an open deck design(like most hondas)and that limits you on the amount of "reliable" power you can make. Still in all,with proper fuel and timing management, I'd say 250-275hp would be okay. As far as turbo selection, there are others here who would better be able to recommend something. I think with the bigger displacement, you'll need something a tad bit bigger that what we use on the SR20. If I'm not mistaken, the new motor is also coil on plug and fly by wire throttle. A standalone is the safest way to turbo it. I'd say a TEC II would be the easiest and safest. Then again, the throttle would have to be redigned. No biggee though. Just get a TB made and run a cable to the pedal. The TEC II will do the rest. Like I said though..this is my opinion. I wouldn't even ATTEMPT to use a piggyback computer or anything like that. That is a bandaid approach.
Travis

Hey Travis you really took what I said to heart on piggybacks and bandaid crap... Glad I have converted you from your FMU days :D

Danny

shhhhh...don't tell anyone!!! lol!
Travis

Danny..by the way..my adress is..

1505 Canal Blvd.
Thibodaux, LA 70301

That's the dealership i work at. Just make it out to me and send it there. I tried to email you, but it wouldnt work.
Travis

wow. Thanks for the good info. I've already called aem and they aren't doing anything for a stand alone system yet for my spec-v, but i know there is other companies out there. but for what you told me about my block and all being that it is an open head as you said. That will help me out trying to find a small but effective turbo. I appreciate you not flaming out like they have the tendency to on the b15 forum.

It has an open deck design(like most hondas)and that limits you on the amount of "reliable" power you can make. Still in all,with proper fuel and timing management, I'd say 250-275hp would be okay.

True. An open deck is only a limiting factor. For a streetcar with a mild turbo it won't be a problem. Your biggest hurdle is the computer and the manifold. JWT has repined/spliced a 2000/01 car to take a 95-97 computer but they had an sr20 in it. The Tec II is also a great option but ultimately more complicated then needed if you can get the JWT thing done. Either way JWT will need to develop a turbo program for the 2.5 engine before you can move forward with JWT. You can get a custom manifold made. Being the first to do a project like this is not for the weak of heart/mind/$. My recommendation is wait a year and let others sort out these hurdles first.

Steve

the guys i talked to said that they could custom fabricate a manifold out of steel or aluminum, and it would be rather pricey. I called jwt and they told me that they were in r&d on the new qr25 motor. For right now i'm going to stick it out and settle for the hotshot combo (header and cai 20hp to the wheels). I also am going to remove the second cat and make it 2 1/4 piping like the guy from the nissan test facility said (14hp to the wheels) and add an aftermarket exhaust, not sure which one yet. That right there should hold me off for a while, not sure how long, but 30 to 40 hp is pretty good for about 600 to 700 $.

header and cai 20hp to the wheels). I also am going to remove the second cat and make it 2 1/4 piping like the guy from the nissan test facility said (14hp to the wheels) and add an aftermarket exhaust, not sure which one yet. That right there should hold me off for a while, not sure how long, but 30 to 40 hp is pretty good for about 600 to 700 $

Consider some dyno time to tune your car using different ignition advance settings after putting that stuff on. Also, I don't know about your car but some people have reported with Nissans it's good to reset the ecu after doing modifications.

Steve

Originally posted by Taintid62
the guys i talked to said that they could custom fabricate a manifold out of steel or aluminum, and it would be rather pricey.

If someone told you they would make you a turbo manifold out of aluminum, run far, far away. They don't have a clue. Aluminum would be a very bad material to use for a turbo manifold.

andris

I second what andris said. Aluminum will not hold up to high temp.

Taint, these guys you're talking to sound like idiots. The first thing that tip me off was they should you only have two choices of turbos, either a t3 or a mitshu. The t3 is a dinosaur and I probably wouldn't use a mitshu turbo either. With turbo cars, you can match up practically any turbo you want depending on the power you want and spool up characteristics.

And making an exhaust manifold out of aluminum would be a VERY bad idea. Intake manifold yes, but exhuast, no. Comparing 6061 aluminum to 304 steel, the aluminum has almost twice the thermal expansion coefficent meaning it'll expand twice as much as the steel will. Since the intake stays relatively cool, you can make it out of aluminum. Even the engine block doesn't get THAT hot because you have coolant running through it. The exhaust manifold gets super hot.... just consider you have exhaust gases like 1600 degrees flowing thru it.

I stay very very far away from those monkeys.

Khiem

I noticed in the new Sport Compact Car (Silvia drifting on the cover) that there was a Nissan wagon in thier coverage of a Japan trade show with a caption that said: ...wagon powered by a QR25DET. It is a white, modified wagon (don't remember the name right now). Maybe there are other alternatives for the QR guys who want to go turbo too now...